Many medical procedures are conducted within or around a body vessel, such as a blood vessel. Such procedures often require the delivery of a therapeutic fluid or agent to a length of the vessel or around the vessel. For example, treatment of varicose veins may require the delivery of a tumescent fluid around a length of a blood vessel to compress the blood vessel around and onto a therapeutic device within the blood vessel lumen. Similarly, to treat varicose veins, a sclerosant may be injected along the length of a blood vessel to irritate and eventually close the blood vessel.
In other procedures, a drug may be delivered along the length of a vessel to affect various tissue in and around the vessel. For example, in renal denervation, which is a procedure to lower blood pressure, a drug may be delivered to the renal artery to affect the nerves in or around the vascular wall.
Delivery of the therapeutic fluid along a length of the vessel is often an issue. For example, therapeutic fluid may be delivered subcutaneously around the vessel, such as injecting tumescent fluid around a vein for varicose vein treatment, which requires multiple injections along the length of the vein. Injection of a therapeutic fluid from within the vessel lumen often requires moving a single needle along and around the vessel lumen to provide enough of the therapeutic fluid. Both are time consuming, requiring significant manipulation and multiple injections at multiple sites. Therefore, a more effective device to inject therapeutic fluid along a length or around a body vessel is needed.